Molecular characterization of emaraviruses associated with Pigeonpea sterility mosaic disease

Sci Rep. 2017 Sep 19;7(1):11831. doi: 10.1038/s41598-017-11958-8.

Abstract

Sterility Mosaic Disease (SMD) of pigeonpea (Cajanus cajan (L.) Millspaugh) is a complex disease due to various factors including the presence of a mixed infection. Comparison of dsRNA profile and small RNA (sRNA) deep sequencing analysis of samples from three locations revealed the presence of Pigeonpea sterility mosaic virus-I and II (PPSMV-I and II) from Chevella and only PPSMV-II from Bengaluru and Coimbatore. PPSMV-I genome consisted of four while PPSMV-II encompassed six RNAs. The two viruses have modest sequence homology between their corresponding RNA 1-4 encoding RdRp, glycoprotein precursor, nucleocapsid and movement proteins and the corresponding orthologs of other emaraviruses. However, PPSMV-II is more related to Fig mosaic virus (FMV) than to PPSMV-I. ELISA based detection methodology was standardized to identify these two viruses, uniquely. Mite inoculation of sub-isolate Chevella sometimes resulted in few- to- many pigeonpea plants containing PPSMV-I alone. The study shows that (i) the N-terminal region of RdRp (SRD-1) of both the viruses contain "cap-snatching" endonuclease domain and a 13 AA cap binding site at the C-terminal, essential for viral cap-dependent transcription similar to the members of Bunyaviridae family and (ii) P4 is the movement protein and may belong to '30 K superfamily' of MPs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cajanus* / genetics
  • Cajanus* / metabolism
  • Cajanus* / virology
  • High-Throughput Nucleotide Sequencing
  • Plant Diseases* / genetics
  • Plant Diseases* / virology
  • Plant Viruses* / genetics
  • Plant Viruses* / metabolism
  • Protein Domains
  • RNA, Double-Stranded* / genetics
  • RNA, Double-Stranded* / metabolism
  • RNA, Viral* / genetics
  • RNA, Viral* / metabolism
  • Viral Proteins* / genetics
  • Viral Proteins* / metabolism

Substances

  • RNA, Double-Stranded
  • RNA, Viral
  • Viral Proteins